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2272512 
Journal Article 
Kinetics and Mechanism of the Oxidation of 4-Oxo-4-arylbutanoic Acids by N-bromophthalimide in Aqueous Acetic Acid Medium 
Farook, NAM; Alhaji, NMI; Mohideen, AMU; Dameen, GAS; Mitu, L; Begam, MA 
2013 
Yes 
Journal of Solution Chemistry
ISSN: 0095-9782
EISSN: 1572-8927 
42 
6 
1183-1193 
WOS:000321283800005 
The kinetics of oxidation of a series of substituted 4-oxobutanoic acids (Y-C6H4COCH2CH2COOH: Y = H, OCH3, CH3, C6H5, Cl, Br or NO2) by N-bromophthalimide have been studied in aqueous acetic acid medium at 30 A degrees C. The total reaction is second-order, first-order each in oxidant and substrate. The oxidation rate increases linearly with [H+], establishing the hypobromous acidium ion, H2O+Br, as the reactive species. A variation in ionic strength has no effect on the reaction rate. The order of reactivity among the studied 4-oxoacids is: 4-methoxy > 4-methyl > 4-phenyl > 4-H > 4-Cl > 4-Br > 3-NO2. The effect of changes on the electronic nature of the substrate reveals that there is a development of positive charge in the transition state. The activation parameters have been computed from Arrhenius and Eyring plots. Based on the kinetic results, a suitable mechanism has been proposed. 
Kinetics; Oxidation; 4-Oxoacids; N-bromophthalimide